ATL: SAM - Remnants - Discussion

[grapealcoholic]

Absolutely ripping now

[Teban54]

Wow, that escalated quickly. Eye temperature up to 11.4C now. And that's in spite of some obvious shear and dry air.

[ElectricStorm]

18L SAM 210929 0000 18.1N 55.3W ATL 120 944

[Sciencerocks]

[InfernoFlameCat]

Hurricane Sam is now at 120 knots and 944mb.

[grapealcoholic]

T#7.0 soon

[skyline385]

T#7.0 soon

ARCHER has had trouble locating the center for 6+ hours now. It's currently at 4.6 Raw and 5.2 CI. It does look a bit messy on IR so can't blame it tbh but the CDO is cooling up again, let's see if it gets to T7 this time....

[storminabox]

Sam is going to be an impressive ACE producer to say the least!

[Fancy1001]

Looks like we’ll be looking at a monster in the morning

[grapealcoholic]

Sam looking mean

[Sciencerocks]

[grapealcoholic]

Looks like the storm isn't fully stacked. Convection should get things aligned quickly

[Teban54]

NE quad has 124 kt FL, 104 kt SFMR. Pressure 952 mb, slightly rose from last recon.
Drop in NE eyewall measured 128 kt mean winds in the lowest 150m, and pretty much 120-130 kt winds throughout. Those can be instantaneous winds, but they do seem to indicate effective mixing down to the surface.

115-120kt is a good guess for the current intensity (it can go either way). I'm surprised Sam has had to deal with dry air and shear for so long - didn't models indicate favorable conditions?

[Teban54]

F. Eye Character: Closed
G. Eye Shape & Diameter: Circular with a diameter of 25 nautical miles (29 statute miles)

Sam has gone a long way from that tiny 7nm eye.

[kevin]

I think the next recon (in about 12 hours) will find an absolute monster. Perhaps our last shot to get an operational cat 5.

[kevin]

I'm looking at the IR images of Sam trying to close off the convection almost like I'm cheering for my favorite sports team . About 2.5 hours ago a very fragile primitive Wring of Sam broke to the E, but now a tiny sliver of deep convection seems to be trying to wrap all the way around and is aided by very cold cloudtops (notice a tiny pink pixel). As soon as Sam gets a stable Wring it can go nuts, but so far every time it tries to do so, it breaks apart again within the hour. Let's hope this attempt is actually successful.

[Shell Mound]

NE quad has 124 kt FL, 104 kt SFMR. Pressure 952 mb, slightly rose from last recon.
Drop in NE eyewall measured 128 kt mean winds in the lowest 150m, and pretty much 120-130 kt winds throughout. Those can be instantaneous winds, but they do seem to indicate effective mixing down to the surface.

115-120kt is a good guess for the current intensity (it can go either way). I'm surprised Sam has had to deal with dry air and shear for so long - didn't models indicate favorable conditions?

Given that Sam is sheared, the FL-to-surface conversion-factor is likely lower than it otherwise would be. I think 105 kt is closer to the actual intensity than 120 kt.

In my view, 90% reduction applies to storms that are juxtaposed with very low vertical wind shear. Neither Larry nor Sam, for the most part, encountered low VWS.

[kevin]

New recon is on its way btw, should arrive in a little over an hour. And NHC went with 950mb/115kt for the 5am advisory.

[Extratropical94]

First SW-NE pass: Inbound max FL 98kt, extrapolated sfc pressure 951.7, outbound max FL 113kt, although there might be some higher readings in the next set of obs.
SFMR not working unfortunately.

Edit: No higher readings in the next set. 113kt max FL

[aspen]

Sam might be attempting a quick EWRC or an eyewall meld, as suggested by a 5z microwave pass.